1. The present invention relates to a quantum interference type semiconductor device having a bifurcated branch conductive channel with a heterojunction in the semiconductor with a band discontinuity.
2. Description of the Related Art
Recently, according to the rapid developments in electronic apparatus such as electronic computers, a high-speed semiconductor device is required. Under this condition, a very-high-speed quantum interference type semiconductor device having a heterostructure is proposed. In such a device, a quantum interference effect of wave functions of an electron at the heterojunction between semiconductor materials with different band gaps, for example, a heterojunction between an undoped GaAs layer and an undoped AlGaAs layer wherein a two-dimensional electron gas layer is produced, is used.
In conventional quantum interference type semiconductor devices having a bifurcated branch conductive channel with a heterojunction in the semiconductor with a band discontinuity for controlling a conductance of the channel by controlling a phase difference of the wave functions of an electron traveling in the channel, the following conditions are necessary to realize a good quantum interference:
1 The energy of electrons injected to the channel should be equal;
2 An inelastic scattering of wave functions of an electron traveling in the channel should be prevented.
In order to realize the condition of 2, a distance between a source and a drain must be less than or equal to 1 .mu.m.